Ex Vivo Bioactivity and HIV-1 Latency Reversal by Ingenol Dibenzoate and Panobinostat in Resting CD4+ T Cells from Aviremic Patients

AM Spivak, A Bosque, AH Balch, D Smyth… - Antimicrobial agents …, 2015 - journals.asm.org
AM Spivak, A Bosque, AH Balch, D Smyth, L Martins, V Planelles
Antimicrobial agents and chemotherapy, 2015journals.asm.org
The human immunodeficiency virus type 1 (HIV-1) latent reservoir in resting CD4+ T cells
represents a major barrier to viral eradication. Small compounds capable of latency reversal
have not demonstrated uniform responses across in vitro HIV-1 latency cell models.
Characterizing compounds that demonstrate latency-reversing activity in resting CD4+ T
cells from aviremic patients ex vivo will help inform pilot clinical trials aimed at HIV-1
eradication. We have optimized a rapid ex vivo assay using resting CD4+ T cells from …
Abstract
The human immunodeficiency virus type 1 (HIV-1) latent reservoir in resting CD4+ T cells represents a major barrier to viral eradication. Small compounds capable of latency reversal have not demonstrated uniform responses across in vitro HIV-1 latency cell models. Characterizing compounds that demonstrate latency-reversing activity in resting CD4+ T cells from aviremic patients ex vivo will help inform pilot clinical trials aimed at HIV-1 eradication. We have optimized a rapid ex vivo assay using resting CD4+ T cells from aviremic HIV-1+ patients to evaluate both the bioactivity and latency-reversing potential of candidate latency-reversing agents (LRAs). Using this assay, we characterize the properties of two candidate compounds from promising LRA classes, ingenol 3,20-dibenzoate (a protein kinase C agonist) and panobinostat (a histone deacetylase inhibitor), in cells from HIV-1+ antiretroviral therapy (ART)-treated aviremic participants, including the effects on cellular activation and cytotoxicity. Ingenol induced viral release at levels similar to those of the positive control (CD3/28 receptor stimulation) in cells from a majority of participants and represents an exciting LRA candidate, as it combines a robust viral reactivation potential with a low toxicity profile. At concentrations that blocked histone deacetylation, panobinostat displayed a wide range of potency among participant samples and consistently induced significant levels of apoptosis. The protein kinase C agonist ingenol 3,20-dibenzoate demonstrated significant promise in a rapid ex vivo assay using resting CD4+ T cells from treated HIV-1-positive patients to measure latent HIV-1 reactivation.
American Society for Microbiology